Brown Trout stocking summary (GLFC)
Colin Lake - MNRF
Glenora Fisheries Station
Lake Ontario Management Unit
Date last updated: 2021-12-11
Data source
These data (1966- 2019) are from the GLFC Stocking Database. Since the new stocking data-entry and viewing portal is currently being developed, data are only complete up to 2019. (Michigan is the only exception - they have 2020 data entered, but i omitted it for the following plots, etc).
These are pretty rough visualizations - just meant to inspire some ideas. There is a lot of work going on to improve the quality of the GLFC stocking data base, but we’re not there yet - this data set is still rough in places.
lifestage
This table shows the age (min and max) of the various Brown Trout life stages, and the time of year (month) that they were stocked. n = number of stocking events of the particular life stage.
| stage | n | min_age | max_age | min_month | max_month |
|---|---|---|---|---|---|
| fry | 9 | 1 | 1 | Inf | -Inf |
| fingerling | 1,375 | 0 | 11 | 4 | 11 |
| spring fingerling | 76 | 3 | 8 | 3 | 6 |
| summer fingerling | 63 | 4 | 16 | 6 | 9 |
| fall fingerling | 808 | 5 | 13 | 7 | 12 |
| yearling | 7,495 | 0 | 24 | 1 | 12 |
| adult | 892 | 10 | 48 | 1 | 12 |
| NA | 2 | Inf | -Inf | 5 | 5 |
Number Stocked (yearling eq)
All lifestages converted to yearling equivalents
Bar Plot - Number by Lake
Bar Plot - Number by State or Province
Mean weight of yearlings by Great Lake
Very quick look at what the data look like - obviously some issues. Check to see if grams entered instead of kilograms in some instances.
Stocking Dates
Average dates of Brown Trout stocking events (yearlings only; averaged by lake and year) 
Map
Stocking events aggregated by stocking site (spring yearlings only). Radius of circle indicates number of fish (1000’s) stocked. A small number (n=7) events could not be mapped due to errors in grid assignment.